In a storage device, such as a memristor, when current flows in one direction through the storage device, the electrical resistance increases, and when current flows in an opposite direction, the electrical resistance decreases. When the current is stopped, the last resistance in the memristor is retained. Further, when the flow of charge begins again, the resistance of the memristor reverts to a value when the memristor was last active. Such storage devices can be formed in an array configuration that includes a plurality of storage devices disposed, for example, in a row and column format. Each of the storage devices in the array can be individually addressed to read or write to the storage device. For example, a row and column can be individually addressed to read or write to a corresponding storage device.